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Subject: Re: [PATCH v7 3/3] drivers/vfio: EEH support for VFIO PCI device
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Alexander Graf <agraf@suse.de>
Date: Thu, 29 May 2014 09:18:45 +1000
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On Thu, 2014-05-29 at 00:46 +0200, Alexander Graf wrote:
> I don't think so :). In QEMU the PHB emulation would have to notify the 
> "container" (IOMMU emulation layer -> PE) that a PE operation happened. 
> It's that emulation code's responsibility to broadcast operations across 
> its own emulated operations (recover config space access, reconfigure 
> BARs, etc) and the VFIO PE operations.
> 
> So from a kernel interface point of view, I think leaving out any 
> address information is the right way to go. Whether we managed to get 
> all QEMU internal interfaces modeled correctly yet has to be seen on the 
> next patch set revision :).

For a kernel interface I absolutely agree, all we care about is the group fd.

>>From a qemu internal, I suppose it makes things easier to operate at the PHB
level for now and we can revisit later if the need arises.

Cheers,
Ben.